1. Field of the Invention
The present invention relates to a combination of a lock and a key, and more particularly, to a lock with adjustable cores and an adjustable key.
2. Description of the Prior Art
The conventional lock generally comprises a cylinder received in a cast, and the cylinder includes a housing, a core and multiple bead units.
The housing of the cylinder is a cylindrical member and has a room defined in a center thereof. The housing has multiple outer bead holes defined through the wall thereof. The core is a cylindrical member and has a keyhole defined therein. The core has multiple inner bead holes on an outside thereof, the inner bead holes communicate with the keyhole. The core is rotatably located in the housing, and the inner bead holes are located corresponding to the outer bead holes.
Each of the bead units includes an outer bead, an inner bead
and a resilient member. The bead units are inserted in the corresponding inner and outer bead holes, wherein the outer bead and the resilient member are located in the outer bead hole, and the resilient member pushes the outer bead whose inner end slightly protrudes beyond the inner bead hole. The inner bead is located in the inner bead hole, and the outer end of the inner bead is in contact with the inner end of the outer bead so that the inner end of the inner bead movably protrudes beyond the keyhole. The inner bead and the outer bead of each bead unit has its own length which is made to be matched with the cuts of the key. When the key is inserted into the keyhole, the inner beads are matched with the cuts of the key so that the inner and outer beads are moved to a position where the contact portion between the inner and outer beads is located at the surface between the core and the housing. Therefore, the key may rotate to rotate the core to unlock the lock.
The length of the inner and outer beads of the existed lock is designed specifically for a correct key. If multiple locks are used, then multiple keys are prepared to unlock the locks individually. However, the multiple keys need a space to store, and most of the keys look alike. Once the key is lost, if a spare key is available, the user needs to duplicate another one, otherwise, the whole lock has to be replaced to prevent unauthorized access to the lock.
The present invention intends to provide a combination of a lock and a key, wherein the cores are adjustable and the key is adjustable so as to eliminate the shortcomings mentioned above.